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\(a.Mg+2HCl\rightarrow MgCl_2+H_2\\ 2Al+6HCl\rightarrow2AlCl_3+3H_2\\ b.Đặt:\left\{{}\begin{matrix}n_{Mg}=x\left(mol\right)\\n_{Al}=y\left(mol\right)\end{matrix}\right.\\ n_{H_2}=\dfrac{18,48}{22,4}=0,825\left(mol\right)\\ Tacó:\left\{{}\begin{matrix}24x+27y=17,1\\x+\dfrac{3}{2}y=0.825\end{matrix}\right.\\ \Rightarrow\left\{{}\begin{matrix}x=0,375\\y=0,3\end{matrix}\right.\\ \Rightarrow\%m_{Mg}=\dfrac{0,375.24}{17,1}.100=52,63\%\\ \%m_{Al}=47,37\%\)

Rượu etylic \(C_2H_5OH\)

Axit axetic \(CH_3COOH\)

\(n_{CO_2}=\dfrac{2,24}{22,4}=0,1mol\)

\(2CH_3COOH+Na_2CO_3\rightarrow2CH_3COONa+H_2O+CO_2\uparrow\)

      0,2                  0,1                 0,2                  0,1         0,1

\(\%m_{CH_3COOH}=\dfrac{0,2\cdot60}{39,6}\cdot100\%=30,3\%\)      

\(\%m_{C_2H_5OH}=100\%-30,3\%=69,7\%\)

a)

\(n_{CO_2}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\)

PTHH: 2CH₃COOH + Na₂CO₃ --> 2CH₃COONa + CO₂ + H₂O

                 0,2<----------0,1<-------------0,2<-------0,1

=> \(m_{CH_3COOH}=0,2.60=12\left(g\right)\)

\(\%m_{CH_3COOH}=\dfrac{12}{39,6}.100\%=30,3\%\)

\(\%m_{C_2H_5OH}=\dfrac{39,6-12}{39,6}.100\%=69,7\%\)

b) dd sau pư chứa \(\left\{{}\begin{matrix}CH_3COONa:0,2\left(mol\right)\\C_2H_5OH:\dfrac{39,6-12}{46}=0,6\left(mol\right)\end{matrix}\right.\)

\(V_{dd}=\dfrac{0,1}{2}=0,05\left(l\right)\)

=> \(\left\{{}\begin{matrix}C_{M\left(CH_3COONa\right)}=\dfrac{0,2}{0,05}=4M\\C_{M\left(C_2H_5OH\right)}=\dfrac{0,6}{0,05}=12M\end{matrix}\right.\)

a.b.\(n_{CO_2}=\dfrac{5,6}{22,4}=0,25mol\)

\(2CH_3COOH+Na_2CO_3\rightarrow2CH_3COONa+CO_2+H_2O\)

       0,5                                                              0,25               ( mol )

\(m_{CH_3COOH}=0,5.60=30g\)

\(\%m_{CH_3COOH}=\dfrac{30}{45}.100=66,67\%\)

\(\%m_{C_2H_5OH}=100\%-66,67\%=33,33\%\)

c.\(m_{NaOH}=50.20\%=10g\)

\(n_{NaOH}=\dfrac{10}{40}=0,25mol\)

\(2NaOH+CO_2\rightarrow Na_2CO_3+H_2O\)

 \(\dfrac{0,25}{2}\)   <    \(\dfrac{0,25}{1}\)                                ( mol )

 0,25                           0,125                    ( mol )

\(m_{Na_2CO_3}=0,125.106=13,25g\)

a) 

2CH₃COOH + Na₂CO₃ --> 2CH₃COONa + CO₂ + H₂O

b) \(n_{CO_2}=\dfrac{5,6}{22,4}=0,25\left(mol\right)\)

PTHH: 2CH₃COOH + Na₂CO₃ --> 2CH₃COONa + CO₂ + H₂O

                  0,5<-----------------------------------0,25

=> m_CH3COOH = 0,5.60 = 30 (g)

=> m_C2H5OH = 45 - 30 = 15 (g)

c) \(n_{NaOH}=\dfrac{50.20\%}{40}=0,25\left(mol\right)\)

Xét tỉ lệ: \(\dfrac{n_{NaOH}}{n_{CO_2}}=\dfrac{0,25}{0,25}=1\) => Tạo muối NaHCO₃

PTHH: NaOH + CO₂ --> NaHCO₃

              0,25-------------->0,25

=> m_NaHCO3 = 0,25.84 = 21 (g)

\(Đặt:n_{C_2H_5OH}=a\left(mol\right);n_{CH_3COOH}=b\left(mol\right)\left(a,b>0\right)\\ a,PTHH:C_2H_5OH+Na\rightarrow C_2H_5ONa+\dfrac{1}{2}H_2\\ CH_3COOH+Na\rightarrow CH_3COONa+\dfrac{1}{2}H_2\\ n_{H_2\left(tổng\right)}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\\ b,Ta.lập.hpt:\left\{{}\begin{matrix}46a+60b=10,6\\0,5a+0,5b=0,1\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}a=0,1\\b=0,1\end{matrix}\right.\\ \%m_{C_2H_5OH}=\dfrac{0,1.46}{10,6}.100\approx43,396\%\\\Rightarrow\%m_{CH_3COOH}\approx100\%-43,396\%\approx56,604\%\)

Ta có: \(n_{H_2}=\dfrac{11,2}{22,4}=0,5\left(mol\right)\)

a. PTHH:

Zn + H₂SO₄ ---> ZnSO₄ + H₂ (1)

MgO + H₂SO₄ ---> MgSO₄ + H₂O (2)

b. Theo PT₍₁₎: \(n_{Zn}=n_{H_2}=0,5\left(mol\right)\)

=> \(m_{Zn}=0,5.65=32,5\left(g\right)\)

(Sai đề nhé.)

\(n_{H_2}=\dfrac{11,2}{22,4}=0,5mol\)

\(MgO+H_2SO_4\rightarrow MgSO_4+H_2O\)

\(Zn+H_2SO_4\rightarrow ZnSO_4+H_2\uparrow\)

0,5                                      0,5

b)\(m_{Zn}=0,5\cdot65=32,5\left(g\right)\)

   \(m_{ZnO}=\) ko tính đc do lỗi đề